State Behaviour of Aqueous SolutionsY Doc. Ing. Ivan Cibulka, CSc. e +420220444063, +420220443782 Accurate measurements of density of and speed of sound in dilute aqueous solutions of organic substances are performed using two experimental setups: automated flow vibratingtube densimeter constructed in the laboratory (density in the temperature interval 298573 K and under pressures up to 30 MPa) and the commercial apparatus DSA 5000 (density and speed of sound in the temperature interval 278343 K under atmospheric pressure). Partial molar volumes and partial molar isentropic compressions at infinite dilution are evaluated from experimental data and analysed from the point of view of structure – property relationships. Group contribution methods for estimation of these two quantities are developed. 

Laboratory of experimental thermodynamics: Phase and chemical equilibria, and properties of mixturesY Doc. Ing. Vladimír Dohnal, CSc. e +420220444297 The research group is engaged in experimental study of equilibria in multicomponent fluidphase systems and related thermodynamic and thermophysical properties of dilute aqueous and nonaqueous solutions of organic substances. To this end, we employ a large variety of procedures of experimental thermodynamics including phase equilibria measurements (vaporliquid, liquidliquid, solidliquid), calorimetric measurements (enthalpy of mixing, dissolution, and reaction), volumetric measurements, and measurements of viscosity and optical properties. Currently, we focus mainly on technologically, interesting systems with ionic liquids (IL), and pharmaceutically active ingredients (API), deep eutectic solvents (DES) and dilute aqueous solutions of volatile organic compounds (VOC) environmental and sensoric significance. In the systems mentioned, we study also other specific phenomena as formation of inclusion complexes or micelles or acidbase equilibria. Longterm effort of the group is devoted to experimental method and procedure development. New methods for determination of limiting activity coefficients, selectivity of nonvolatile separation agents, mixing enthalpies and solubilities belong to our achievements in this direction. 

Laboratory of Membrane Separation ProcessesY Doc. Ing. Karel Friess, Ph.D. The laboratory is specializes in the study of the transport of gases, vapors and their mixtures through flat polymer membranes. The selfdeveloped permeameters are used to determine the permeability and diffusion coefficients, respectively. The diffusion coefficients of gases and vapors in polymers are evaluated from the (gas or vapor) sorption kinetics. Sorption experiments are performed gravimetrically via Mc Bain spiral balances. These balances are also used to determine the sorption isotherms and the sorption coefficients of gases and vapors in polymers. 

Computer simulations of complex systemsY RNDr. Mgr. Jan Heyda, Ph.D.b Jan.Heyda@vscht.cz e +420220444257 → web In terms of computer simulations, we study the behavior of biomolecules in aqueous solutions, their thermodynamics and kinetics, action of salts and osmolytes. Grounded in the knowledge of molecular interactions we can rationalize the stability of protein native state, determine the solubility, or quantify the electrophoretic mobility. Moreover, for fast qualitative description of polymer and protein thermodynamics, we can determine in silico key parameters, which are further applied in thermodynamic models. Our approach is based on defining system key properties, applying an simulation protocol of optimal sampling efficiency, and finally evaluate the target property via statistical analysis of simulation data. 

Surface and Interface PhenomenaY Ing. Štěpán Hovorka, Ph.D. → web a) Experimental study of the concentration and temperature dependence of surface and interfacial tension leading to an extension of a database with physical properties (e.g. solutions of organic nonelectrolytes in water and aqueous solutions of inorganic salts and denaturants of proteins are the subject of the study) b) A creation of a correlation equation (based on a theoretical model) that enables a quantitative description of mutual relations among physical properties of mobile phase interfaces (surface and interfacial tension) and a bulk of liquid phase (activity coefficients of components in the solution) c) Experimental study of wettability of solids by liquids focused on pharmaceutical topics d) Collaboration with ICPF of the CAS and IMC of the CAS on a project aiming at a resolution of racemic mixtures to particular enantiomers e) Experimental study of physical properties of polymer membranes immersed in liquid solutions. Permeability and diffusion coefficients (i.e. kinetics of mass transport through the membrane), overall sorption of solution in the membrane and preferential sorption of particular components (phase equilibrium) and swelling of the membrane are measured. This activity is an extension (no duplication) of a research of Laboratory of membrane separation processes of Dr. Friess that is focused on membranes touched by gases and vapors f) Experimental study of solutions of surfactants 

Statistical thermodynamics and molecular simulationsY Prof. RNDr. Jiří Kolafa, CSc. We investigate systems of many molecules by theoretical as well as pseudoexperimental methods using classical statistical thermodynamics. While applying theoretical approaches as diagrammatic techniques and integral equations, we make use of modern methods of computer algebra. The pseudoexperiment includes molecular dynamics and Monte Carlo simulations. We study a broad range of systems, from lattice models (e.g., of ice) to simple molecular system (hard spheres) to atomistic models (water and ice, salts, solutions). We also develop simulation methodology and force fields. 

Statistical theory of inhomogeneous fluidsY Mgr. Alexandr Malijevský, Ph.D. → web 

Laboratory of Enhanced Spectroscopies and NearField MicroscopyY Prof. Dr. RNDr. Pavel Matějka → web 

Laboratory of phase equilibria. Measurement and prediction of solubilitiesY Doc. Ing. Karel Řehák, CSc.b karel.rehak@vscht.cz e +420220 444 039 The group focus on experimental determination of solubilities of solids, liquids and gases and on computational treatment of data that involves correlations and prediction of solubilities by means of equations of state and other thermodynamic models. The laboratory is equipped with experimental apparatuses (usually of own design) for measurement of phase equilibria and analytical instruments (GC, UVVis spectrophotometer, KFcoulometer, vibration tube density meter). An apparatus for determination of vapour–liquid equilibrium (at low pressures), an apparatus for measurement of gas solubilities (0.1–5 MPa) and various experimental devices for determination of liquid–liquid and solid–liquid equilibria are operated in the laboratory. Correlations and predictions of solubilities are based on utilization of models for the excess Gibbs energy (Wilson equation, NRTL, UNIQUAC, UNIFAC, NRTLSAC) and equations of state of the PCSAFT type. Computational treatments of data are usually done by selfmade programs. 

Applied ThermodynamicsY Doc. Ing. Květoslav Růžička, CSc. → web 

Theoretical Photodynamics Research GroupY Prof. RNDr. Petr Slavíček, Ph.D. Laboratory of Theoretical Photodynamics aims at modeling interactions between photons and molecules. Due to advancement of laser technologies, light can be these days controlled in time, energy, or position with unprecedented precision. Our goal is to understand how we can control the molecules via the light. In our work we investigate a wide range of topics, e.g., biomolecular photostability, atmospheric photodynamical processes following the excitation of the molecules, interaction of molecules with high energy radation or photoionization and chargetransfer reactions. At the same time, we aim to model molecules beyond the gas phase, investigating finite molecular aggregates or molecules in the condensed phase. Part of our work is also necessarily devoted to the development of new and more efficient techniques of molecular simulations. We develop new methods for simulating electronic spectra, new quantum chemical approaches or novel approaches for modeling solvent. 
iduzel: 24735
idvazba: 31140
šablona: stranka
čas: 30.9.2020 20:29:48
verze: 4723
uzivatel:
remoteAPIs:
branch: trunk
Obnovit  RAW
idvazba: 31140
šablona: stranka
čas: 30.9.2020 20:29:48
verze: 4723
uzivatel:
remoteAPIs:
branch: trunk
Obnovit  RAW
Physical Chemistry
Updated: 5.1.2016 12:22, Author: fchi